Active flow control technology using the effect of momentum addition by non-thermal plasma has extensively been investigated in the region of aerodynamics especially aeronautics. The plasma flow control device consists of discharge electrodes set on a object surface and a high voltage power source. The advantages of this technique are its ability to induce very thin flow inside the boundary layer, rapid response using electrical control, and the mechanical failure-free resulting from its simple configuration. In this paper, the mechanism and features of the plasma flow control and its applications are reviewed.

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The electrochemical polymerization of pyrrole on an ITO (indium-tin oxide) coated glass electrode with an insulating film of poly(vinyl alcohol), PVA produces a flexible composite polymer film with electrical, optical and electrochemical properties very similar to polypyrrole (PPy). The rate of electrochemical polymerization depends on the diffusion of the electrolyte across the PVA film to the ITO electrode. Especially, the solvent with hydrophilic nature easily penetrates into the PVA film. By applying this new process, we demonstrate a unique method to form electrically conductive pattern in PVA film. It will be possible to develop electrodes for electrical stimulation of the nervous system using conducting polymer, PPy. Then, by using similar technique we have fabricated poly (3,4-ethylenedioxythiophene), PEDOT/PVA composite films and investigated their electrochemical basic properties.

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This paper describes analyses of electric fields in eccentric two spherical conductors induced by a uniform ELF magnetic field utilizing the equivalent multipole-moment method with re-expansion technique (RE-EMMM). Although an approximated formula has already been derived by Tarao in this situation, it has been limited to the first order approximation. Here, the authors mathematically derive a general expression of governing linear equation for unknown multipole and local coefficients. Furthermore, we derived the first, second, and third order electric field formulae by manually solving the linear equations. It is confirmed that the accuracy of the first order formula is almost the same to that of Tarao's. On the other hand, the accuracies of the second and third order formulae are confirmed to be more precise.

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The electro-oxidation of formic acid, 2-propanol and methanol on Pd black, Pd/C, Pt-Ru/C and Pt/C has been investigated to clear the reaction mechanism. It was suggested that the formic acid is dehydrogenated on Pd surface and the hydrogen is occluded in the Pd lattice. Thus obtained hydrogen acts like pure hydrogen supplied from the outside and the cell performance of the direct formic acid fuel cell showed as high as that of a hydrogen-oxygen fuel cell. 2-propanol did not show such dehydrogenation reaction on Pd catalyst. Platinum and Pt-Ru accelerated the oxidation of C-OH of 2-propanol and methanol.
Slow scan voltammogram (SSV) and chronoamperometry measurements showed that the activity of formic acid oxidation increased in the following order: Pd black > Pd 30wt.%/C > Pt50wt.%/C > 27wt.%Pt-13wt.%Ru/C. A large oxidation current for formic acid was found at a low overpotential on the palladium electrocatalysts. These results indicate that formic acid is mainly oxidized through a dehydrogenation reaction. For the oxidation of 2-propanol and methanol, palladium was not effective, and 27wt.%Pt-13wt.%Ru/C showed the best oxidation activity.

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Various studies have been carried out on the particle composition of ionized Argon containing excited atoms in a steady state. In some of these reports, the thermodynamic and transport properties were calculated under conditions of chemical equilibrium and LTE (Local Thermal Equilibrium). However, there have been few reports of the particle composition and thermodynamic and transport properties of ionized Argon under conditions of non-chemical equilibrium in time change. In this study, the time taken for the system to change from a non-equilibrium state to an equilibrium state was elucidated for an Argon plasma arc under changing temperature conditions (from 300K to 10,000K). First, the particle composition of partially ionized Argon plasma changing from a non-equilibrium state to an equilibrium state was calculated using a chemical kinetic method at 3,000K-25,000K, without taking radiation into account. The thermodynamic and transport properties including mass density, enthalpy, specific heat, electrical and thermal conductivity and viscosity were calculated based on a Chapman-Enskog first order approximation using the values obtained for particle composition in the equilibrium state. These results showed that the method is valid. Second, the particle composition and thermodynamic and transport properties were investigated under conditions of changing temperature (from 300K to 10,000K). It was shown that the particle composition changed from a non-equilibrium state to an equilibrium state in the order of μs. The thermodynamic and transport properties were separated with the changing or not changing category in non-chemical equilibrium in time change.

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We proposed a low-cost plasma process technique to fabricate narrower front electrode grooves on a single crystalline silicon solar cell, in which the surface discharge operated at high-pressure etched the silicon nitride film of 150 nm thickness on a silicon layer. The results showed that the surface discharge could effectively etch the silicon nitride film in a short time and that a high etching rate more than 3000 nm/min was obtained. The narrow and uniform grooves with the width of less than 70 μm were obtained when the pressure in a chamber, the back electrode length and the etching time were 152 kPa, 2 mm and 10 s, respectively. The narrower electrode groove could be obtained when the back electrode length was short and the pressure was high.

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C-axis-oriented zinc oxide (ZnO) thin films were prepared on Inconel substrates by rf magnetron sputtering technique. The ZnO film characteristics were evaluated under pressures of 10.0 to 300.0 MPa and frequencies of 0.1 to 30 Hz at room temperature. The deviation from the linearity of charges with pressures for the ZnO films was within 0.52 % of a full scale at 300.0 MPa, which indicated a good linearity between 10.0 and 300.0 MPa. Furthermore the ZnO films were evaluated under combustion pressure in a single-piston 90 cc engine rotating at 1900 rpm. The waveform of the ZnO films was similar to those of a commercial sensor. It is demonstrated that the ZnO films have a good possibility as combustion pressure sensor elements.

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Recently, polymer nanocomposite has been attracting much attention as an emerging insulating material. In this paper, we measured space charge distribution in low-density polyethylene (LDPE)/MgO nanocomposite at room temperature and 90°C. At room temperature, while a huge amount of packet-like charge moving from the anode to the cathode is observed in the base LDPE, such packet-like charge is not observed in the MgO-added nanocomposites. On the other hand, at 90°C, while injection of negative charge from the cathode is dominant in the base LDPE, the filler addition significantly suppresses the injection. As a consequence, space charge is barely formed in the 2-phr MgO-added sample at the two temperatures.

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